Creates a request with a full-text predicate added to the eventual set of already applied predicates.
// SELECT * FROM book WHERE book MATCH '...' var request = Book.all() request = request.matching(pattern)
If the search pattern is nil, the request does not match any database row.
The selection defaults to all columns. This default can be changed for all requests by the
TableRecord.databaseSelectionproperty, or for individual requests with the